Connector assembly



April 24, 1962 .1. J. BERTRAM ETAL 3,031,638

CONNECTOR ASSEMBLY Filed March l1, 1960 United States atentf ice 3,031,638 CONNECTOR ASSEMBLY Joseph J. Bertram, Norwalk, and Jack E. Antes, Old Greenwich, Conn., assignors to Bumdy Corporation, a corporation of New York Filed Mar. 11, 1960, Ser. No. 14,310

2 Claims. (Cl. 339-217) This invention relates to electrical connectors, and more particularly, to contact retaining means for connector assemblies.

It is commonplace to manufacture connector assemblies made up of a plurality of individual contacts. Of late these contacts have been made individually insertable and removable from the assembly; permitting the contact to be first connected to a conductor and then inserted into the housing of the connector assembly. Similarly the contacts and their conductors may be removed from the assembly and replaced. This individual contact assembly feature generally requires a retention spring to lock the contact in place. Unfortunately, these springs, if made large and rugged, do not permit miniaturization of assembly with the maximum number of contacts in the smallest area; and if made small and fragile rapidly deform, taking a permanent set, and fail after only a few insertions and removals of the contact. Further, many of these springs permit the contact to be twisted out of its mounting hole, a rotational pull on the contact camming the spring into depression.

It is, therefore, an object of this invention to provide a Contact retention spring which will permit both miniaturization of assembly and good interlocking, and yet allow for a multiplicity of insertion and removal operations of individual contacts in a connector assembly.

A feature of this invention is a retention spring having a single spring tab or linger and which is adapted to tilt or cant on its associated contact both during insertion of said contact, and when the contact is subject to an axial pull, either with or without concurrent rotation.

These and other objects and features of this invention will become more apparent by reference to the following description taken in conjunction with the accompanying drawings, in which:

FIG. 1A is a View in elevation of a contact having a contact spring and a retention spring in accordance with the principles of this invention;

FIG. lB is an end view of the contact of FIG. 1A;

FIG. 2A is a view in elevation of the retention spring of FIG. lA;

FIG. 2B is an end View of the retention spring of FIG. 2A;

FIG. 3A is a view in elevation of the contact spring of FIG. 1A; and

FIG. 3B is an end view of the contact spring of FIG. 3A. Referring to FIGS. lA and 1B, reference character 1 indicates generally a female or socket type contact having at one end a central bore 2 adapted to vreceive the projection of a male or pin type contact, and at its other end a central bore 3 adapted to receive a conductor. A peep hole 4 is provided to permit inspection of the extent of the insertion of the conductor into the bore. The contact also includes a ridge 5, a neck portion 6 having a window 7 onto bore Z and a neck portion 8. Disposed on neck portion 6 is a substantially C-shaped spring 9 having central dimple 10. Dimple 10 projects through window 7 into bore 2. Disposed on neck portion 8 is a retention spring 11 having a single upstanding tab 12.

FIGS. 2A and 2B illustrate the retention spring 11, which is substantially of C shape. As shown in FIG. 2A, the upstanding center portion or tab 12 of the retention spring 11 is not parallel to the central axis of the spring. FIGS. 3A and 3B illustrate the contact spring 9, which 3,031,638 Patented Apr. 24, 1962 V Y 2 is substantially of C shape. The center portion of the C includes an inward-going surface 10a and a transition surface 10b. An inward-going dimple at the center of the C might also be used.

Referring again to FIG. l, in assembly the contact spring 9 is snapped into neck portion 6 so that inwardgoing surface 10a projects through window 7 into bore 2. Surface 10a will thus press the pin contact against the socket wall when the pin is inserted into bore 2, and ensure good mechanical and electrical contact between the pin and socket contacts. Transition surface 10b is adapted to guide the inserted pin under the inward-going surface 10a. Spring detent 11 is snapped onto neck portion 8. It will be noted that the neck portion 8 is of greater length from shoulder 8a to 8b, than the included spring 11 from edges 11a to 11b, and so spring 11 is adapted to cant on the neck 8 until its edges 11a and 11b contact shoulders 8a and -Sb respectively. A conductor (not shown) is inserted into b ore 3 and secured therein by suitable means, suchas crimping. f

Finally the connector is inserted into its mounting hole 13, with bore 2 end leading. As spring 11 passes through hole 13, it both cants on neck portion S and has its tab 12 depressed, the gap between the ends slightly increasing adjacent 11a and decreasing adjacent 1-1b. The depression that tab 12 undergoes, however, is not as great as it would be if the Whole spring 11 was not able to cant, and thus not exceed the elastic limit of the spring material. Thus the residual set that the tab 12 develops as a result of its depression is not as great. When the connector is pushed fully into hole 13, and ridge 5 abuts the shoulder 14 of the mounting panel, tab 12 snaps up to at least a height where its tip 12a is above the level of the hole 13. If the contact is now pulled slightly, as by a strain on the conductor, tab tip 12a abuts the shoulder 15 of the mounting panel and the spring 11 is rocked back into place, swinging tab tip 12a even' further above the hole. If the stress is increased the tab tip v12a will expand in the hole 13a increasing its locking power and removing any set induced by its insertion through hole 13.

The contact is now held in hole 13 by ridge 5 and tab tip 12a. If the contact is twisted, the contact will rotate within both the hole 13 and spring 11. There is no tend-v ency for the tab to be cammed back into hole 13 or to chew up the hole.

To remove the contact assembly from the mounting, an extraction tool is inserted into hole 13a to depress tab 12a, permitting the convenient withdrawal of the contact from hole 13.

Although FIG. 1 illustrates a femal type contact, obviously a male type contact may be similarly mounted.

The invention has thus been described but it is desired to Ibe understood that it is not confined to the particular forms or usages shown and described. The same being merely illustrative, and that the invention may be carried out in other ways without departing from the spirit of the` invention, and therefore, the right is broadly claimed to employ all equivalent instrumentalities coming within the scope of the appendent claims, and by means of which objects of this invention are attained and new results accomplished, as it is obvious that the particularly embodiments herein shown and described are only some of the many that can be employed to obtain these objects and accomplish these results.

We claim:

1. A connector assembly comprising a dielectric housing, said housing including a mounting hole having a constriction of a given diameter; ametal contact having a contact-insert-portion, of less than said given diameter for insertion through said mounting-hole-constriction; said contactdnsert-portion including two shoulders and a section of reduced diameter therebetween; a retention spring disposed substantially coaxallyabout said section ofreduced diameter between said shoulders, and having a length shorter than the distance'between said shoulders; a portion of said retention spring normally projecting above the surface of said contact-insert-portion; the arrangement being such that upon said contact-insert-portion and said retention spring being inserted into said mounting hole said retention spring and said mounting hole constriction having a mode of operation wherein the inner surface of said constriction both depresses said retentionspring-projecting-portion and tilts said retention spring on said reduced-diametersection away from Aits coaxial relationship with said'reduceddiameter-section, said retentionspring-projectingportion returning to substantially its normal height above the surface of said contact-insert-portion upon said retention spring being passed through and beyondsaid mounting hole constriction.

2. A connector assembly according to claim l further including:v a portion on said contact having a diameter of greater than said gi'ven size for preventing overinsertion v of said contact-insert-portion; and wherein the full insertion of said contact-insert-portion disposes said retentionspring-projecting-portion axially beyond said mounting hole constriction, whereby said retention-spring-projectingportion in its returned-to-norrnal height prevents withdrawal of said contact-insert-portion from said mounting hole.

References Cited in the tile of this patent UNITED STATES PATENTS 

